Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
ban hanh » ban hang
duc ban » duc tan, duc van, dua ban
y nang » ly nang, v nang, may nang
qua ca » qua cac, qua cua, qua cai
ca duc » cao duc, cua duc, ca dua
va cua » va chua, via cua, ma cua
ca cua » co cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((y nang) or (ky nang)) x ho. hieu qua ca duc ban hanh ((va cua) or (ca cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y nang) OR (ky nang)) x ho. hieu qua ca duc ban hanh ((va cua) OR (ca cua)) triet.
• Adding a wildcard symbol may retrieve word variants: thu sach ((y nang) or (ky nang)) x ho. hieu qua ca duc ban hanh ((va cua) or (ca cua)) triet*.